Just include the eprint option in your bibtex file, and it will appear in your paper citation after the paper reference. RevTex4 (Phys Rev) also has built in support for this. Much easier to use than doing a reverse arxiv search from the reference!

(For those that don't know, you can get pre-formatted BibTex entries automatically from the arxiv: on the paper abstract page click "SLAC-SPIRES HEP", then click "BibTex"- which includes the arxiv reference)

IMHO the same should work for apj_hyperref.bst - it seems to work for me.

(2) nat2jour.pl needs to handle bibtex broken long lines

bibtex cuts lines longer than 79 characters, putting %\\n at the break, so that other programs can glue the pieces back together later on.

nat2jour.pl 2004/10/06 glues all lines back together, but does not remove these % signs. Since latex considers % as a comment, this causes a problem for long URLs like from the ADS urls (in principle, \\url and \\href know about % or _ in urls).